This disclosure generally relates to advertising campaigns, and more specifically to pacing bids for advertisements on an online system.
Advertising systems may present advertisements to users of various computing devices to provide revenue to providers of content and other services to the computing devices. These advertisements are typically selected from advertising campaigns run by various advertisers via an auction. Advertisers may have certain goals when planning a new advertising campaign (“ad campaign”). For example, an advertiser may have a goal for the number of times an advertisement is presented to clients of an online system (i.e., the number of “impressions” of the advertisement), user interactions with an advertisement, user interactions with a third party site or product advertised by the advertisement, or other actions by the user that may be caused by viewing the advertisement. Payment to the advertising system for placement of an advertisement may be contingent on meeting one of these goals. The goals on which payment is based are termed “conversion events.” In addition, an advertiser may specify certain constraints, or attributes, of an advertising campaign such as targeting characteristics for a target audience of the advertisement, or a budget for the advertising campaign.
An advertiser bids in the auction using a bid amount associated with advertisements in the advertising campaign. As an advertising campaign proceeds, the bid amount used in the auction for that ad may be adjusted and the ad campaign may end when the campaign reaches its budget. The bid amount used in the auction is termed a paced bid, and may be adjusted to pace selection of the advertisement according to the budget and time for an advertising campaign to run. An advertiser may specify a compensation amount that the advertiser will provide to an online system when the conversion event occurs resulting from the advertisement. However, advertisements must be selected for a user in advance of the conversion event's occurrence due to electronic delays, failure of a system to actually retrieve the advertisement, verification of the conversion event, or the delay of a user performing the conversion event after viewing the advertisement. As a result, an advertising system may continue receiving notification of conversion events after a budget has been reached. In this example, the advertiser's budget is exceeded. Alternatively, the online system may stop presenting an advertiser's ad prematurely by mistakenly expecting that additional conversion events will occur thereby resulting in a situation in which the advertiser's budget is not spent before the campaign ends. Thus, this delay between advertising selection and identification of conversion events may result in “jerky” pacing of an advertiser's bid in an auction as the pacing overs or under-adjusts. This may cause over or underspending of the advertiser's planned budget thus resulting in inefficient use of an advertiser's budget for presenting advertisements in an advertising campaign. In some examples, the advertising system loses revenue or must ‘write off’ revenue for related to conversion events achieved after the budget is reached.